Can i replace the broken check valves with the pvc type that lowes sells?
does anyone know?

sure. Prior to cutting out, verify flow direction of check valve and same when glueing new one in. You may want to check to see if it's air or water and the psi it requires to open it. That can matter. Try not to reduce pipe size, and you'll need a short length of pipe and two couplings.
If you need a specific check valve for air/ or water / or psi, a local spa store should be able to get what you need or there's plenty of us here that can get what you need.

i hope they work, they are spring loaded, but i can blow thru them to open them, the ones i took out had no spring,they were free floating, im not really sure what psi the spa pump puts out.

if the check valve required a certain psi it would be labeled on the check valve.

in case anyone needs to know...........yes they do work!