Like the others said, do it. A Teres 135 is so much better than a P3 your head will swim. If it's still too much $ consider an armless Nott' Horizon for about $1K. Easy to mount a Rega on that too.
You can also upgrade your RB300 with parts from OL, Expressimo, etc. This will take it well above the stock model. I'd suggest a VTA collar first (Expressimo's is best IMO), then a rewire, then an upgraded end stub, then a new counterweight. You can do each of these steps as funds become available. Final performance compared to an OL? I'd ask Twl. :)
If you order a Teres 135, tell Chris Brady you want a 25mm arm hole. If you just say "Rega" he'll drill 24mm and you'll have to ream it out for the VTA collar.
You can also upgrade your RB300 with parts from OL, Expressimo, etc. This will take it well above the stock model. I'd suggest a VTA collar first (Expressimo's is best IMO), then a rewire, then an upgraded end stub, then a new counterweight. You can do each of these steps as funds become available. Final performance compared to an OL? I'd ask Twl. :)
If you order a Teres 135, tell Chris Brady you want a 25mm arm hole. If you just say "Rega" he'll drill 24mm and you'll have to ream it out for the VTA collar.