Heat tape on the cool side in a rack setup is going be the best option if you aren't able to run a heater I would think. That's what I'm planning to do because I'm not able to run a heater year round in my current place and it's the best option I've been able to come up with.
As for Boaphile, I would search reviews on him before ordering and look at reptile basics. They have flat packed racks that are easy to assemble. I've dealt with Boaphile twice and both times have been unpleasant and my girlfriend at the time ordered a rack from him only to have it delayed more than 2 months and arrived damaged. Just my 2 cents.