1933 Manila to Germany With Postal Seal

It's anybody's guess on what postal seal issue was used on this cover.
It can be one of the three yellow or lemon yellow seals issued before 1933:
#OX6, #OX7, or #OX9.  It cannot be #OX8 as it from the picture, it is not perforated.
Only the high bidder will know. 

I consider covers with USPI period postal seals as very scarce to even rare.
I am not at all surprised at its closing price. In the early 1990s they were selling
for above 200 bucks already. (eBay US$ 232.49)