Here are a few places to get started.(NO affiliation) Give each one a call and explain your problem. Perhaps one of them will direct you to an appropriate service person.
If you can find a local company that services bobtail delivery trucks, they can probably help you out as well.
Suburban, Heritage & Amerigas are usually just distributors. Although they may sell a few appliances, they are not normally in the RV service side of the industry.
http://www.northsidepropane.com/
http://www.thumbtack.com/fl/tampa/hvac/propane-natural-gas-equipment-cleaning-installation-repair
http://www.gasservicetampabay.com/Appliance_Repair_Tampa_FL.html
http://manateervrepair.com/services/
Good luck,
Gary