I think xrp may mean they have this type.
Whenever we see a coin of an unreported date for a well-known type, I think we always need to ask “what else could it be?” So, for the other coin mentioned, that was claimed to be a 1727, it turns out to be a 1712 with lots of wear on the date, and the privy mark mistaken for a 7.
I admit that in the case of your coin, it looks more like it could be 1727. However, because of the wear, we cannot be sure. Here is a 1723 Gelderland silver gulden where I have “worn away” the bottom of the date, and I think it could easily be mistaken for 1727:

Edit. I found another 1723 which gives some additional evidence. On this one I have again “worn away” the date on tyhe obverse, but the reverse has the thin G in BELG, different from the thick G in 1 G and ARG. This matches the shapes of these letters on your reverse (of course it could be possible the die was used at a later date, so this does not absolutely exclude other explanations).


My best guess is that you may have a 1723.