In my experience, if you have Costar-style stabilizer clips on the board, you can either use a shorter balance bar and Costar-style inserts, or a slightly longer one and ALPS-style inserts on the keys.
If the board has ALPS-style stabilizer wires, no go. I just went and tested (board: Focus 2001; keycaps: from a Ducky 1008XM) -- on the biggest key I can test easily, the right shift, the stabilizer wires miss the inserts entirely. On other keys, they don't allow enough travel to seat the cap on the key.
I'm also unsure if you can swap the Costar wire... the ALPS clips are so far apart on right shift, that I'm not sure the Costar wires will fit. I suspect what we'd just need is to use Costar inserts, but a custom bent wire.