If you want to be a cheap bastard but get a very exact pull weight, I've done this before....
Pull the barreled action out of the stock so you can get clear access to the trigger.
Raid your spare change dish for quarters, they weigh exactly 0.2oz each.
Throw a bunch into a plastic sandwich bag, and tie a length of dental floss with a loop on it.
See whether you can slowly lift the bag off the ground while hanging it from the trigger, without setting it off.
Add $$ or adjust trigger as needed.
I like to run my match rifle with the trigger set at $16.25.