any help with this piece of silver is appreciated

[joe gargasz]

Hello
I have a oval deep silver bowl that is halmarked on the bottom underside of the lip. The halmark appears as follows a horses head facing in twords center, then a mark that looks something like this " (^) with marks inside.
then two full bodyed herons facing in twords the middle boxed.
Under these marks is SCRIBED NOT STAMPED
HM
SALE

On the opposite end on the underside of the lip is this stamped number 2170 1/2
The piece is 3/16 of an inch thick overall and is heavy. The design on the top side is a scalloped border around the oval bowl lip with a heavy rope and flora motif, all appears to be hand worked.
Any information on origin, age and maker would be greatly apreciated.