I been using automotive RM 700 spray can primer. This primer work very good. It easy to sand and paint stick on very well. Ofcourse K-36 is better. But the problem is cleaning up after each use and some the primer go to waste.
So pray can work fine for me.
Pay $9.00 a can. Which is little more expensive than K-36 count by ounce. But end up cheaper by not wasting primer and safe time.

You can get this from automotive paint store. Look for store that carry RM Diamont paint. I like to use RM Diamont brand over PPG. It spray on much smoothler than PPG.

Brg,
Tam
X body man.