The price seems reasonable. Took a 4th and 5th to get Eugene Monroe a couple years ago- would think there would be a similar price for Norwell who is better, but plays at a less premium position.
Availability on the other hand is a little more questionable. Carolina isn't swimming in cap space for 2018 (They have about 11mil projected for next year- enough to sign Norwell if they wanted to- Baltimore has about 10mil for comparison) but they have placed a heavy emphasis on keeping a good line by extending Trai Turner and signing Matt Kalil (who is bad, but apparently not bad enough for Carolina). My gut instinct would be that Carolina wouldn't part with Norwell because there is a clear emphasis there on protecting Cam and building a strong run game and Norwell is a really important part of that line. Carolina doesn't have any back-ups on their OL who would be good enough to justify trading Norwell and they haven't spent much draft capital on the position lately. If they lose Norwell, their options are Moton or Daryl Williams (who are both competing at RT for now) or Silatolu (who has spent half his career on IR) or an array of ineffective journeymen.
Sorry for the long write-up, I'm just bored, but I would assume Norwell isn't on the trade block.