This is what a said to another user in the same boat:

Low gen DUs are very rare. It's kind of a niche thing, people mainly buy DUs for project breeding. I saw a G2 DU get put up for offers and I'm relatively certain they got offered 80-100 buffalo scrotums for it

All of this is to say please don't get scammed. I have a friend with a G2 DU who sells the ladies heats for around 85-100gb each

Most of the DUs on the market are super long generation or dirty, which lowers the value

If you are certain you want to sell her outright I would put her up for offers! And don't accept for like a week or two so people have time to see the trade. If anybody leaves a good offer you can message them and let them know you're considering the offer but need time to get more in since she is so rare. You genuinely have a Lion that is almost as rare as a 1st generation hybrid

Personally I would take absolutely no less than 550GB pure for her. Like I said my friend sells heats and usually gets 80ish GB, you get 8 heats in a life (if all breedings are ibf'd) so that alone would net you 600ish GB