Dominator spigotted head

Yes, this is assumed to be the case, though on the 850 the gap between the bores is small but uses a composite gasket. It maybe possible to make a composite gasket theses days that would do the job, but the copper version works well. 

NOC  spares shop, page 6  Engine parts  £7.50, Is that what you need?. Have to say that leaks happen if you don't tighten down 3 times ,and if it still comes loose throw away those cheap SS head bolts and fit the old plated bolts!. Use a sealer round pushrod tunnels,oil drain and stud/bolt holes.