Grafs has about the best Harvester pricing and if you buy a bunch the $7.95 flat rate shipping is ok.

I highly recommend you try these first though. They are cheaper than Crushribs and typically work really well in CVA bores unless yours is very tight. I use them in a true .500 Douglas ML barrel and they load/shoot great.
https://www.grafs.com/retail/catalog...productId/5481

The Red Crushribs are really large OD. Normally they are only used in very loose bores.

BTW your V1 was never designed to shoot BH209. Its a very good idea to modify the breach plug for best reliability with BH209.
CVA Hex Breechplug Modification