I'd be looking at someone to do it before even thinking about making my own gear to do it.
No point wasting who knows how much time, effort and money trying to make a half-decent DIY job to cut one, never mind 50, when you could by one cut neatly and accurately for a few quid, and 50 for a few pence.
As they are local to me, and have done similar for me in the past, both for work and personal stuff, my first phone call would be to
https://dobsongasket.com/
No point wasting who knows how much time, effort and money trying to make a half-decent DIY job to cut one, never mind 50, when you could by one cut neatly and accurately for a few quid, and 50 for a few pence.
As they are local to me, and have done similar for me in the past, both for work and personal stuff, my first phone call would be to
https://dobsongasket.com/