My friend gave me this stamped wrench, heavy gage 5/32" thick, 7 1/2" long, 1 1/8", 1", 3/4", 11/16" 5/8" to 7/16" OE, no manufacture's marking. any ideas?...

That looks like the sizes needed for changing out gas bottles, eg. on a cutting torch, but tough to say without a size reference.

Yes.

Below a Uniweld W06 wrench (after market replacement I think)

It would be interesting to see a thread on the varieties of this tool.  I've seen a few myself.

Thank you guys!!  now I remember seeing something like that hanging on gas bottle racks...

There are some of these wrenches that are quite well made.  I have/had one that was forged and marked AIRCO.  It seems that there are quite a few different sizes and shapes.

Mike