Just seen this on eBay.
https://www.ebay.co.uk/itm/1841-halfcrown/183076706631?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649
Both reverse and particularly obverse are completely "wrong" - bust, date numerals, legend font. I believe it is yet another of these replicas that are all over the numismatic world, yet worry that someone is going to get seriously burnt. Bids are already well over £300.
Do members concur?
There is also a genuine, slabbed one, on the site Buy it Now for £3900, which backs up my opinion. See https://www.ebay.co.uk/itm/VERY-RARE-1841-HALFCROWN-VICTORIA-349/222843579237?hash=item33e2832b65:g:3fYAAOSwsm1ZvnU4
Hope no-one here is bidding on the replica one!!