My husband and I have begun shopping for a ring for our 10th anniversary in December. I've narrowed it down to a style like the platinum Tiffany 3 stone circlet, however we don't really want to pay retail Tiffany prices ($4800).

Ebay kind of scares me, even though I've found a couple listed with diamonddr16 ($3250), whom I've read some here recommend.
http://www.ebay.com/itm/Tiffany-Co-Platinum-Circlet-Diamond-Ring-PT950-55Ct-Sz-7-5-/360898477662?pt=US_Fine_Rings&hash=item540739be5e
I've also found one on idonowidont.com (asking $3100). But it sounds like that site isn't very popular on these boards? - https://www.idonowidont.com/diamonds/tiffany-co-three-stone-circlet-engagement-ring
I've also gone to a local jeweler who showed me something similar that they could custom order ($2900), but I'm not sure I like it as much as the real thing. Plus, it would not be returnable, being a custom piece and I'd really want to try it on first.

Buying second hand does not bother me at all as long as I know I'm not getting scammed. Are there other options that you can suggest for this style of ring? If I make an offer on the idonowidont.com ring, what would be the lowest I could go without insulting the seller?

Ebay kind of scares me, even though I've found a couple listed with diamonddr16 ($3250), whom I've read some here recommend.
http://www.ebay.com/itm/Tiffany-Co-Platinum-Circlet-Diamond-Ring-PT950-55Ct-Sz-7-5-/360898477662?pt=US_Fine_Rings&hash=item540739be5e
I've also found one on idonowidont.com (asking $3100). But it sounds like that site isn't very popular on these boards? - https://www.idonowidont.com/diamonds/tiffany-co-three-stone-circlet-engagement-ring
I've also gone to a local jeweler who showed me something similar that they could custom order ($2900), but I'm not sure I like it as much as the real thing. Plus, it would not be returnable, being a custom piece and I'd really want to try it on first.

Buying second hand does not bother me at all as long as I know I'm not getting scammed. Are there other options that you can suggest for this style of ring? If I make an offer on the idonowidont.com ring, what would be the lowest I could go without insulting the seller?