This one is good for you then two 1 TB blocks on different backbones for $15: https://portal.usenetprime.com/cart.php?a=add&bid=37.

Or this one 3 TB for $15 (4000+ retention): https://billing.blocknews.net/signup/blockfriday

Or this one 6 TB for €15 (2800+ retention ): https://bulknews.eu/en/ and use the code bf241. Bulknews is on Abavia backbone.

Or this one 4 TB for $25 (4633+ retention): https://newsgroupdirect.com/member/billing/?plan=ce57&planid=233&yes_tracking=1

Or this one 500 GB for 10.50 till January 3 (3000+ retention): https://usenet.farm/

The retention is not accurate, it is probably more than this.

You would also need an indexer, each indexer offers different things, there are indexer that offer a trial you test them.