My thoughts are very similar to yours GhostHawk.
You can buy .25 caliber boatail air rifle molds from NOE right now.
I already own molds very much like the premium Air Venturi brand 9mm projectiles that sell for 25 cents each.
I have read that there is a technique in pumping these high pressure pumps. They need some dwell time at the end of each stroke, so the air can get through small passages. Both on the up and down stroke. Should get some first hand experience on that today.
I could see my self without that information, grabbing the pump and going to town like I was pumping up a bicycle tire 50 year ago.
Fed-Ex delivered the rifle about 9:30 yesterday, Hope the pump and pellets arrive early too.