On the subject of beaching legs, I might have some input to help others.
In the process restoring "Lyra" V-2941, I made some legs for the boat that enabled me to apply both interprotect and antifouling coats (7 in all) without having to move the pads on a conventional setup. What I did was to fasten an L-bracket via four bolts using the amidship stanchion base area (using the same holes through the deck). This bracket was then bolted thru a 4 by 4 treated piece of lumber with two 1/2" bolts. The end of the 4 by 4 then rested vertically on the ground on some plywood pads (to adapt to ground softness). The boat did not budge for a whole week with just these two legs holding it up. I did not however get on the boat too much, especially to the sides...
So, it seems like that area is really strong in the Vega, and as long as you use a good backing plate (made of aluminum preferably), you should be able to fashion some kind of bracket that would be permanently mounted, to which one could then attach beaching legs (maybe made of telescoping aluminum extrusions?)
Hope this is some help to the current discussion,
Cedric and Melissa
"Lyra" v-2941
Charleston, SC