This is “original” z-slider that came with the x-50 Journeyman Original (not “Pro”). One of the screws has stripped (that is the Allen key won’t catch any more). So I have a few questions:
Try McMaster Carr
Thank you for your reply.
Here is what I searched and filtered. Any suggestions on which one?
Our local Ace Hardware would have these as well no fright cost.
Pat
Thank you. I’ll go there first!
You may want to get the screw out first. There’s a good chance that the damage is to the threads in the hole, not just the screw. If so you could be looking at something like a heli-coil.
Yes, the of course I’ll need to get the screw out first 
I was quite careful when I tightened them the last time so I hope it’s not anything worse than the stripped head!
If it’s just the head where the allen wrench fit into you should be ok. You’re not going to know until you get it out. It’s possible that the threads are messed up was my point. Hopefully it’s not a big deal and a new screw is all you need. I’ve done things like use a chisel on the outside edge of the screw to tap on it to loosen it (I’m not sure if I would want to do that though) to drilling the center and using an easyout. But if you snap an easyout while in the screw you now have a hardened piece of metal you can’t easily drill to deal with.
My first option would be to try to use an SAE allen wrench slightly larger and see if you can force it into the screw. Another option would be to cut a slot with a Dremel and cut off wheel to use a slotted screwdriver. Hopefully you get it without too much work. If you don’t have some I would get good quality allen wrenches (both the ball driver and straight head). They are pricy but I’ve had really great results with the Wadsworth Super mini ratchet set.
I hate slotted heads. I usually just cut a couple of relatively parallel sides on the heads and then use a wrench or vise grips to turn the head.
Thank you @Dr-Al for all of your inputs. I’m going to trying a few things as well as make a trip to Ace hardware. I’ll let you know how it goes.
Thank you @JimHatch. I may just go there. Not sure if there is enough space around the screw to try what you’re suggesting but I didn’t think if it, so thank you.
Why is it so difficult for onefinity to provide screws for users to purchase. A while back onefinity sent out a questionnaire on what would we like to see them improve in 2024 myself and others suggested a care package for your cnc i.e. (replacement screws). Would this even be possible for onefinity to achieve?
But probably not the low-profile ones (at least my local Ace Hardware doesn’t).
We have 2 Ace Stores in my area (Southern Utah) and they both have massive fastener sections and for sure the low profile SHCS you mention as well even large selection of screws made for guns. I look for some off the wall stuff sometimes and always find what I want there.
The stuff is all Hillman mfg, actually pretty pricey but still beats McMaster when you consider freight.
Thanks, Pat