Its great that your husband is a collector and you asked us to help you. Here are a couple of suggestions:
The He-man and Beastman statues as well as the Skeletor Bust are available to purchase from Pop Culture Shock. They are a little pricey but well worth the price on the pieces.
Castle Grayskull from Matty Collector will be available to purchase in November.
You say he is a He-man and Turtles fan. Stop by the Power-Con website and pick up some t-shirts featuring He-man and Turtles characters.
You can also pick him us some hoodies from 80s tees. They also have Horde Logo and Skeletor designs.
Well I hope this helps with your Christmas Shopping.
Take care B and thanks for looking.