CHIINESE BOWL/WRECK

Hello
Assistance with information welcome.
I bought this Chinese bowl in London about 7 years ago. I have mislaid the paperwork and can only remember bits of information.

I remember it was from a wreck, I think in South China Sea c.1790 (?). I was told it was auctioned at Christies in Amsterdam some years previous to the date I purchased it (so around 2000 or earlier).

I was told the marks around the foot of the bowl were to record it for auction.

The bowl is 6cm high, 12cm wide at top, and 4.5cm wide at base (foot).
There is a slight rim and the bottom of the bowl is flat. It sits on a foot.

The colour is light green I think called Celadon.

The decoration is light, difficult to see in blue/grey. Inside bowl there are two brush lines one at top of rim and one at base. Inside base in bowl is a Chinese? character (I tried to photograph). Outside are 4 identical characters around the outside - like a "h" or "b' open at bottom of letter, with a mark across the top of the line.

The glaze goes right down to the bottom of foot.

The black ink marks on the outside foot mentioned as being associated with auction read "HC90-Gm250" a gap and then "Gm 250"

In side base of the foot, running around the inside edge are incised or stamped characters, but I can't make any out really (tried to photograph)