There's no reason to doubt that it's a Lemond frame, here's why : the Wt. is typical
As a tig'd 853 frame outs it as a late '90s or beyond, all the same dimensions.
Earlier ones 853 and otherwise were lugged, it those which had even sizes.
You've meas. it incorrectly perhaps. A lugged would meas. 56 CT by 56.5 or so TT
55cm, later frames were 55CT with long TTs, 57(or so) TTs always meas. CC
So do try to meas. it again. I've meas. these myself, owned 'em and recall data.
The point is that he nor others focused on precise meas. just to be handy.
One Al. frame I own and rec. ck'd out meas. slightly larger than it's 53cm ought to.
The paint looks unfamiliar but the type of paint appeared as LeMonds right off.
Knowing all that's been available (within reason), in tig'd 853, I can't possible come
up with a more rational idea. LeMond has a data base, if nothing else.
I could of course, stab at a comment.. "generic" or such but that'd be silly.
Shops don't care or know enough to venture a guess, they've no stake in it.
When I ventured into shops that had Trek which owed LeMond, it was as if I
was talkin' about a Fuji... "different division Mister, sorry" so much for that.....
Do the ID # thing VIA the Site, it comes-up as the first entry.