Back in 2001, AIC authorized a series of 5 "all 
hand paint" or AHP cels in editions of 500 for, 
I believe, about 50000 yen.  I don't know 
whether or not the actual painting was done by 
AIC artists.  The top 4 cels in the jpeg are the 
ones they made, other than the chibi Belldandy 
you have.  I think a place called Anime Depot 
was the official distributor, but the old link I 
have for them is no longer working.  They also 
sold  AIC-authorized AHP reproductions of 10 or 
12 AMG hanken cels in smaller editions for about 
5 to 7 times that price.  For example, the 
bottom cel was listed for 360000 yen, although I 
don't know whether anyone actually paid that.