SR5 1999 saddle height screw replacement (help) needed

While cleaning and setting up my old SR5 I just noticed that gunk and dirt had jammed one of my saddle height screws. It cannot move. The hex is almost rounded from all the trying.

Tried soaking it in 3in1 overnight with no luck. I need a replacement screw ASAP.

Im in Australia so the Ernie Ball page will not let me purchase the screw directly from the company.

Any ideas on how to get a replacement?

Thank you so much!!