I really don't think it's Taka, for a few reasons.

First and foremost, did Taka *ever* wear a high-
collared outfit like that?  All I can recall for 
him is the brown vest/white buttonshirt combo, 
and the red buttonshirt and white T-shirt combo.  
I do think he wore something else at the 
beginning of OAV II, but I can't recall what it 
was.  ^^;

Another thing is that the nose is rather rounded, 
and actually has nostrils painted.  Hardly any 
characters in the OAVs escaped the pointy-nose 
treatment (especially not Taka), and I don't 
recall seeing nostrils painted on any FY charater 
in TV/OAV at all (maybe on Taiitsukun).

And the last thing is that yesterday, there were 
two other seemingly non-FY cels on Art Shop 
Rose:  the first one in the top row, and the last 
one in the bottom row.  They're both gone, but 
the first one was the same character as the cel 
you're contemplating, and the first thing that 
popped into my mind was, "what's this doing in 
the FY section?"

I'm no FY expert, but it's my opinion that it's 
an accidentally misplaced cel.

-Zenjirou