It's an SPF so you know it's good quality. I would estimate the reserve price will be in the mid 40's or higher, a "typical" price range for an SPF. I prefer the SB (351 in this case) but many people prefer the BB (427, 428, 460). It doesn't say but PROBABLY has the IRS rear suspension, which many people prefer. Expect to pay top dollar for a car like this.
Comparing Cobras/Prices is always a good bet. Here's one to compare. It's a Classic Roadster offered by Don Scott, so you know the quality is good. The C.R.'s were longer than "standard" (which I prefer for a little more room) and this one has a BB (which could a "good thing").
CR 427 Cobra
The large variance in price from one Cobra to another has a lot to do with "reputation". WHO built it and HOW becomes the "unknown" in many cars. As a result an EXCELLENT Cobra may sell for "less dollars" because the builder is not known, the frame may be a "one of" custom job, etc. Some GREAT buys are out there, but the "risk" factor increases as the price drops and you have to be "sharp" to understand a "good buy" when you see it.
D Scott and DV (Ed Combs) have excellent reputations as "builders" for instance. Their cars will sell for more than an identical car built by an "unknown".
Ernie