By the time Shimano had gone to 7 speed they had eliminated the claw from most of their mid and high end derailleurs. You have two options:
1. Use a modern Shimano, entry level, 7 speed derailleur with claw, like a Tourney.
2. Take a Shimano 7 speed derailleur of your choice and attach a claw from a donor derailleur. You'll lose about 3mm of travel unless the claw is offset but most deralleurs usually have about that amount of over travel. Most integrated dropout hangers are also about a millimeter or so thicker than a claw hanger, so you can regain some of the lost travel by placing a washer betrween the claw adapter and derailleur, if necessary. Just be sure it's not so thick as to prevent the B-screw from engaging the the stop on the claw adapter. Depending of the length of the claw, maximum cog size may not be quite the same as the derailleur's specs. And you may require a slightly longer axle or relocation of the cones on the axle to get a bit more open end on the drive side for full axle nut engagement.