Perhaps not scarce according to Scott, but scarce based on my experience. Just filled the spot courtesy of
ebay.
I have two examples of the R7a DT (SCV $400) and have seen several other examples in dealer inventories over the past several years. The slightly less expensive R7c (SCV $350) on the other hand, has eluded me. Up until last week I had only ever seen one other offered for sale since I started collecting revenues. Either my timing has been off, or the R7c is considerably more scarce than its imperf sibling. They're just not out there. Either the R7a DT is overpriced or the R7c is underpriced, in my opinion... and it's not like I've encountered scads of the former.
The example I picked up isn't the greatest centering in the world, but it's sound. It came in for well below half my maximum bid, so I was quite pleased. Very stark doubling too.
