Best Of

I spent about $575 just on the parts (including binding posts, though) to rebuild the crossovers in my much simpler, red-headed stepchild RTA 15TLs a couple of years ago now and I continue to be blown away by their sound. Even if it is $300-$400 per speaker for the DIY cost, I would think the 1Cs would be worthy of the expense. Another ~$600-ish, total, for the VR3 plug-and-play version (if you get a discount by not going direct and not through eBay) doesn't seem out of line, either.

The @VR3 XO also has much better inductors. The Jantzen C-coils are not cheap and are fantastic inductors. The Supra Rondo wire is also more than a few dollars. There are more than a few man hours in his work.
To have a plug and play install XO is awful nice ☺️ they're no shortcuts in his work.

Go online and price it out yourself.

My ebay prices are 20% higher due to ebay fees