I guess another way of converting extra points to basic points is by bidding for an upgrade in an SK mileage run. By that, you're possibly spending only 350 EUR on a GO-ticket to ex-Scandinavia to PVG, SFO, MIA, LAX etc, but by putting in maximum bids, you could get upgraded to class Z and earn 12K basic points each way. But then there's always risk you won't get upgraded. And upgrades at check-in-counter won't change booking class.

There are many J-deals with MS out of CAI and TUN, but you'd have to stomach angled flat on most (if not all?) flights. Considering your proximity to CAI, one quite nice deal at the moment is CAI-IST-JFK with TK in J which should net about 18K points at about 1050 EUR ai.