Unknown Oriental Pewter Objects

Wow. Interesting pieces. I haven't seen these before myself, but I have a suspicion. From the size you mention and the weight you suggest, I suspect that these are Torpedo Bottle stands. Torpedo bottles are so called, because they have a rounded torpedo shaped bottom. The idea is a combination of many. The main one is that these bottles were Corked, so it forced the owner to keep them stored on their sides. This keeps the liquid inside in contact with the cork so that it wouldn't dry out and leak. It also made it a pain to drink from because, once opened, you couldn't very well put the rounded bottom bottle down. Therefore a number of designs came out to hold these open bottles at the table, and I suspect that this is one. The shape prevents the holder from tipping over and it sounds like it would accommodate different designs of these bottles (universal holder). If you can confirm this, these stands typically sell for about $130 +/- each. Some sort of tableware is where I'd start looking, anyway. They may even be some sort of fancy napkin holder. Hope this helps!