If you have absolutely no access to clone only ogs the casper is a good place to start. IMAO many breeders are not working with the real cuts they think they have so you'll find a lot of seed lines that may pass on visual traits but you won't get that "loud" bouquet or head rush potency. I've ran OG seed packs from Archive, Aligee, Bodhi, Cali Connection, DNA, etc, etc. I've had reputable seed companies on the nuts for cuts they had previously claimed are exclusive to them..lol. It seems DNA/Reserva Pravada has a very professional operation so they probably still have all their original cuts. The original kosher kush was a knockout and probably one of the best from seed I've seen. Their og 18 is pretty good but you'll find more of a sour kush than a true og. If you are a fan of archive I'd say Valley girl and kirkwood would be your two best bets with hell raiser and casper a close second. I've been around the SF valley, Norcal and San Diego cannabis scene since the early 1990s and to me it comes down the SFV, Tahoe, True and Larry. All seed og's are based indirectly off of these 3 strains and if you find a great pheno it would resemble one of them. Any seedline based off of TK or faceoff will be SFV dom (they are both sfv s1 seeds...might get some arguments on that one from people who believe fairy tales), your larry and true hybrids will be your highest sativa.. lankiest and most "loud," and the tahoe is going to be the highest yielding and most fuel/kerosine. They all have a good blend of lemon kerosine funk as I'm sure you know but you want that STENCH in a seed form. Some will say ghost or poison are the original cuts and some others will claim a super dank og cut that goes around as TK is from Florida in 1990..lol. These are all super dank s1's you can generally trust the seedlines off but you'll see a drop in potency to under 25% unless the sample is prepped.
DNA kosher/#18, Rare Dankness scotts/leroy/starkiller and Cali Connection tahoe/buddha tahoe are great places to start. I see a lot of companies that I was super impressed with their genetic stable like GGG where my plants were absolutely beautiful and frosted to high hell but just didn't have that smell/potency. Don't go by online hype, try to see the background on the cut. For potency F1 or S1 seedlines over backcrosses always!!!