Remember the load on the foot block is TWICE what it is on the jib sheet proper, because it turns through 180 degrees (doubling the shear load). This means on my H25, calculating the jib-sheet load at approximately 1000 lbs (max) allows for Schaefer 3-series or 5-series blocks on the lead, but something much bigger for the foot.
I am contemplating mounting two 7-series cheek blocks on the coaming back there; but have not decided on the angle and location just yet. In the meantime most of us probably use snatch blocks hooked into the toerrail track; but this will bugger up the aluminum but good in no time.
Wichard makes an eye fitting that bolts into the toerail just for this; but they want megabucks just for that. A cheaper solution is, once you know where to put it, getting one of the West Marine u-bolts and mounting it in the toerail-- pull out one bolt, drill a hole for the other leg of the u-bolt, and press it in with 5200. I did this in numerous places on my boat. With this you can use snatch blocks.
I would recommend sliding a piece of water hose up onto the snap shackle to keep it from grating on the inside of the toerail, however.
Never underestimate loads on a boat, particularly for any kind of turning block. The failure mode is small bits of aluminum and stainless steel flying off into the air with you in the way.