David, I get them from tawnadoairguns, it the same guy that sells them on ebay. I pay with paypal, since he's in great britain. He's been trying to keep them in stock, but they go quick. He ships very quickly.
And you'll want the TO84 model. They're the lowest 30mm. Perfect fit for that scope.
I've been putting an old scope base screw in front of the rear ring as a recoil lug, and forfeiting the sportsmatch pin. Then I clamp the front ring until it barely slides, then slide it forward until it bottoms out where the tikka receiver rail tapers up. This gives good ring spacing, and give two forms of recoil lug, haven't had anything move yet, up to a .270 in recoil. Hope this helps,
