Might be a bit optimistic for a 3350. Think when they bought it it was attached to a 6920/30. https://hrntractors.com/product/used-machinery/spearhead-twiga-pro-830m-12005312/
You might find that's in the unsold lots at Cheffins. £7kMite be a bit optimistic on the price as well. I’ll email them and see.
Cheers pal