Long while back, I did a cheapo cosmetic restore on a '46 Willys Jeep (still have it on my dad's farm). I found some original spec military steels that had rust issues around the stem holes. I simply wrapped a piece of leather around the valve stem (tube) and 10 years later, still holding strong. I don't really recommend this approach on a road going vehicle, but for the farm, not a concern for me.
Anyway, I would weld in a patch and then re-drill the stem hole. Opposite side or original location. Either way would be fine.
