well there is a less expensive and easier to do than tig welding have
you ever tried alumiweld
I was designed just for this sort of thing and it is stronger than the
original aluminum ,a buddy had got some to try it and he told me it was
fantastic he took an old tranny casting that the mounting tab was broken
off (the tranny was a junker ) and then he tried to take a hammer to
make it come off ,he said he broke the old case and knocked the
alumiweld but it took a nice chunk of the original material with it ,so
now he uses it to fix all the little aluminum repairs around his place
and on his vehicles he says it's easier and cheaper to fix an engine
bracket then to hunt one down at a junk yard ,
I researched it a lil bit here the military had used something very
similar to it years ago for they needed something to do field repairs to
fix minor failures like brackets and certain components getting cracked
,or broken off and they didn't like the idea of having a vehicle being
pulled back to replace a minor part or to have a welding crew to get at
it ,so they looked for something they can use quickly and easily and
that anybody can do and this is what they got and they need a propane
torch and a stainless steel wire brush to use it
if you want the addy I believe it is alumiweld.com but if thats not it
you should be able to find it in a search
good luck