Hiya paul
yeh it's a shame but like so many other sites, the plough had/has priority. At least we are fortunate in having a record of what was there.
As for the stones, I believe that Tees Atchaeology has them. I keep meaning to go over to Hartlepool and see if I can have a look, they must have a pretty huge collection of cupmarked stones especially from the coastal barrows and monuments.
There are some nice collections of stones in the Whitby and Scarbrough museums too and a couple at Margrove Park.