Hello again, this is the honeywell cross reference and technical specifications web site for that controller.
as you can see it is still down, I cannot do anything reliable for you until they get it back up.
That said, it is possible to adapt or jury rig any number of aquastats to replace the one you have, it can get complex, and I do not recommend it for a wide range of reasons, including safety reasons.
It is also nearly 100% likely that the overload, intermittent short or wiring size error that is causing the current aquastat to burn out will burn out whatever replacement you select.
I can call Honeywell for you on monday if you like if their site is still not up... let me know if you can suffer that wait or not. We can go from there.
A bit about myself, I am 75 years old, with 55 years in the boiler business..owned my own company with 27 staff and have thousands of repairs and larger projects under my belt, both hands on and in supervision of staff. I know what works and what doesn't. None the less depending on how many wiring and controls adaptions you are up to, I can locate an other aquastat to replace the one you have. It will be monday though before I can make any calls.