Sure just search "cruise control" in the softail forum and you'll find solutions.
Of course the solution is going to cost you; around $1000-1200 US dollars.
After those desiring cruise sees the cost they just stick with the throttle lock.
have the brakeaway on my switchback and LOVE it.. works really great and well worth the money I spent.. stole it off of ebay for $80 shipped and another $10 for a hardware kit from brakeaway as some screws were missing
If you read at the bottom of the part description it says that it fits Touring Bikes not Softails. To use something like that you're going to need more than just the handlebar switch, i.e. new ECU and Throttle by Wire set up which will cost you $$$.