Just drill one out of a block of the hardest wood you have lying around. On a drill press, if you have one. But- the bigger issue with pocket hole attachment is usually leaving a square bottom on the countersink portion of the hole, and having pan head screws that won't split out the piece you are attaching, rather than how you drill the pilot holes. You can also use a slide jig for a router will make decent countersink holes for pocket screw attachment. But honestly- it is likely that dowels or biscuits would be a better choice for whatever you are doing if this sort of thing is a mystery to you.

Just buy the Kreg jig, you’ll thank me later