Thank you for all your advice this was really helpful, I read it multiple times.
I bought some decent tools from leathercrafttools.com I think will get the job done, 1-5mm round hole punch, 4 and 5 mm oval punch, and a 35mm english point strap end punch. I can't really invest in multiple sides of bridle to cut from ATM so I'm going to go with buying some 1 1/4" straps from buckleguy where I'll also get my hardware.
Anyone know If I go with heel bar buckles will I have enough material left at the end of my straps to make keepers from? They're 55-60" long.