decided to build a shopping bike in my new man cave,want to fit a basket to the surly ice cream truck fork do i get a integral basket with struts like a wald or a seperate rack and fasten a basket to it.

Separate basket. You can take it into the shop with you and cut down on plastic bag usage.

Plenty of people simply use zip-ties to fix a Wald basket to the rack that suits the bike best. Then (repeating SR's point) you can use a tote bag like these, ideal. A few brands make then in Wald basket sizes (generally not cheap though)

Cheap option - I used a liberated Tesco-type basket on one of these cheap mini racks. Had it on there for years, works really well.
https://www.ebay.co.uk/itm/252762490516