ALESSI silver plate

Hi, I’m johnny and I have recently happened upon a couple of pieces. they are a silver plate teapot and tray they are marked “offinca ALESSI epss Italy”
and they have a bird over the letters I have determined that they are from the bombe collection and with that bird mark are probably from the 50’s. or earlier. What I would like to know is how to find out what they might be worth, any help would be greatly appreciated.

I have always found that eBay’s completed auctions are very good indicators to value as they show what people are prepared to pay. I note that there are currently a couple of Alessi plated items in their list, on of which is a Bombe teapot. This sold for £(GBP)62.70.