If you are having that many flats you should check into having the tires
foam filled.

I think I will. After a quick google search, it seems this is
something that has to be done at a shop, not a DIY project. Are there
DIY options out there? If not, whats an aproximate price for a tire of
this size? (23x10.5-12) Obviously easily worth $50-70/tire as thats
the going rate for a replacement, and this would obviously last much
longer. Currently both tires are flat, but have very good tread on
them, would it be possible to fill these, or do I need to buy new ones
to fill?

Thanks for the info!
Bryan