Our boy was exactly the same!
Fishing rod style toys are great. Also, if he bites, don't pull away, just exert gentle pressure towards him, and he will let go. Don't react to the scratching. If you can, cut his nails (I did this all the time and now can touch our boys feet with no issues, helpful as he's now a night prowler and comes home with all sorts stuck in his pads!)..
Our boy was 5 weeks when we found him, so we had to teach him what was ok and what was not. With the scratching, we just stopped playing and looked at him if he did it too much, and he soon learned to stop. When he did stop, we would give him a 'slow blink' and say good boy, he soon cottoned on that was a better reaction!
At around 12 weeks though ankles became his favourite prey, he would hide under things and jump out when you walked by.. Big bed socks were the answer, and just keep walking (carefully, of course!)..
Good luck!