Well I'd say checkout what MindsetOverhaul has first.
fill gaps with anything Griffin or I might have. (sorry Griffin not trying to do you out of a sale. just seems logical since MSO sounds like he's loaded.)

I have the following but I'm only parting with them because you've shown interest. as such I'll have to charge $7 each to make back most of their cost to me.
I have Transformers G1 Volume 3 issues 03, 04, 05 and 06. 2 carded and 2 loose, all in near mint condition.

otherwise If you still don't have a full set check out these listings on eBay.
Not sure exactly what's in this one. I'd ask for full cover photos.

I think this is from the third volume

the complete (I'm not sure you'd have to research it) Armada Series

This seller was selling these years ago I'm sure. it's not quite the complete set, they also produced issues 9 and 10, though they are hard to find, very hard.
Apart from this seller, I haven't seen most of these Volume 3 issues for sale for years. If they are in good nick and for real this is an incredibly good price for all these.

volume 1 and 2 have been collected into TPB's, Volume 3 never was and as such is harder to find the whole story. Hope that's some help.