In a small gun shop today I found a box of these. This is not the familiar red and yellow box but an all-yellow one, printed “For Holland’s 500-.465”. The box is in good condition, all 10 rounds are there and don’t appear to have ever been removed from their paper wrapping. The cartridges are in pristene condition. I almost bought them as an investment but then thought that I should try to get a feel for their worth and for what demand exists for them. Any thoughts or advice?