If you really like the Custom, screw what they think and get it, you will not regret it.
I don't know why they said it doesn't 'fit' you. I have an 07 Custom and I'm only a bit over 5' 7" and except for when I have to push it back wards (up hill!) I don't have any problems riding it. I couldn't completely flat foot it when it was new except when the wife was on the back or I scooted forward a bit.
But as the seat got broken in and I got more used to the weight of the bike, it just doesn't bother me.
If I do have an issue with it its that the pegs seem to be just a hair too far away for extended runs. I can't quite relax or my feet feel like they want to fall off. I can however put my heels on top of them if I sit forward on the seat, but I'm ten years older than you and the knees don't like that for too long.
I have been giving serious consideration to having somebody like "Mean City Cycles" (http://www.meancitycycles.com/) fix it to move me forward an bit and narrow the front a little so it fits me better. But I'm not giving up on it, the damn thing is WAY too much fun.
As for no one in your area not renting or demoing bikes. I find the latter part of that statement a bit odd. There are 6 (maybe 7) Harley dealers all within a hundred miles of my house and they have all had or will have open house demo ride days within the last couple of months to show off the new 09 models. And they will no doubt do it all over again in the spring, they it do every year. So I suggest you go to the Harley company web site and look up all the dealers within driving distance and see if they are having one. Most have web sites with events listed and I think the main company web site used to have a schedule showing where they are having them.

 

Thanks for the info, I think I will get the custom. They do demo here but no FXSTC to sample.
I,ve always liked that style of bike, but I need to ride it first before I buy.

 

5'11' with a 30" inseam and it fits just fine. I did put some 4" risers on mine that had a 2" setback and it is perfect now. You will love the Custom. Ride safe.

 

I'm 5'9+ , 175, I have 01 FXST with drag bars (which is harder reach than the mini apes) and it is a GREAT fit, if you are comfortable riding motorcycles.

If you have not ridden for sometime, then maybe you should consider something smaller first.

 

I also replaced the bars but it went nearly the opposite direction. Because of an accident (fell off a roof) I have nerve and circulation damage to my right arm. The mini apes felt fine but made my right hand and wrist hurt and go numb after 20 or 30 miles.
As for getting a smaller bike if you haven't riden in a while I have to take issue with that. The Softail line of bikes are very easy, even tame bikes to ride. I had only ridden a limited amount for a number of years before getting mine and was to tell the truth a little afraid of the thing.
After all its much bigger, heavier and not nearly as manuverable as the bikes I was more accustomed to. But it only took a few miles to feel very relaxed on it. Its a very easy bike to get used to. Provided you have at least a reasonable amount of experience.
Just don't expect it to keep up with the lunitic fringe who like to push crotch rockets to the limits. But I have even managed to surprise a few of them.
The Custom may not be the end all bike for cutting up the turns with. Anyone with a reasonable amount of talent and time in the saddle could eat one alive on almost any Sportster in a real race. But its no slowpoke either and as long as you respect its limitations and keep the speeds below eighty the kid on the crotch rocket next to you will think there's something wrong with his bike.
Course if he's riding on my right side he may have some hearing issues after a hard run as well.

See if you can try a used Standard or Nightrain as they are about the closest things to a Custom. The FL versions like the Fatboy, Deluxe, etc. would not be the greatest test as the heavier front ends and floorboards make them feel differently.
Failing that I'm not sure what you could try that's going to feel like one. But look around, there has to be other dealers around and if your lucky one 'might' have a used Custom (07 or 08) they will let you try.

 

5'10" and my 07 fits well for me

 

5'7 and 165lbs with 29 inseam. Flatfoot it no problem and while it's a tall bike no issue at all handling it. Great bike.
Ron