Graham Phantom Mounting Bolts - Where to Get Them?

So I’m a notorious roller. Tubes. Cartridges. Tonearms. Cables. If it screws or plugs into something, I’m gonna roll it, and often (this extends into relationship difficulties too). Apparently I’m also really bad at somehow losing all these various fastening screws & bolts. Now I’ve somehow managed to lose one of the four LONG threaded bolts (Allen socket head) used to secure the Graham Phantom II Supreme base to an armboard.

Do any of you wise analog angels know where these bolts could be sourced, or at least what the specs/dimensions are? I’ll try contacting Graham after exhausting all other options, because I’d like to find a replacement before the next Ice Age. It’s a really nice tonearm that deserves to be used. I even have three (3!!) wands for it. Surprised I haven't lost one of those yet.