The 22" barrel ones I have seen have been around $400. Minty just out of box may touch $500 for the right buyer. If you have modified anything and that includes screwing in a sling swivel in the buttstock it goes down. Unless you have a top end scope, little impact on price. Wonderful rifles. I think the early to mid 1970's were some of the best fit and finish on these. My 30-06 is 1972ish vintage and shoots great.
These prices are based on what I have seen in Alberta over the past while and will likely vary by region. You really should keep it!