Quoted:
+1
I paid $2000 for mine over six years ago.
Great find.
I can make you cry...
I had bought an HK43 for $600 arond 1989. Fast forward to the AWB, and Cali had implemenetd their ban with an enumerated list (specific models). This list did not include the HK 43 (early variant of the HK93), and someone in Cali offered me an insane amount of money for the HK43, which was still legal under their ban. With the money I got from that deal, I replaced it with another HK93 with A2 and A3 stocks, a P7M10, and hade a few hundred left over in change.
So, looking at it from a pure perspective of money out of pocket, I got an HK93A3 and P7M10 for about $300.
ETA: To the OP, nice job on getting the HK93. You can get the Xtrema another time, and you've already got ~ $700 in equity in your new rifle.