It does seem a tad excessive, but I suppose if you gotta have it, you gotta have it ...
I was planning a few Leu bids, but checked prices before I went to bed last night and decided against it!
This campgate reverse is interesting in that these fancy fluted columns strongly suggest a city gate rather than an army camp gate. There are known surviving city gates, such as the one from Jerash, that do have this type of architectutral detail. I've written a bit about this before on FORVM.
https://www.forumancientcoins.com/board/index.php?topic=125014This is the only reverse die for the Rome P-R campgate series that has these columns. It's also known from a few museum specimens (ANS, BM, Vienna), and I also saw one sold on eBay back in 2006. Other than the Vienna specimen, these are all paired with this same D6 obverse die. The Vienna one has a D7 bust.