Parsley would be fine. Alternatives..... pineapple chutney, creamy grain mustard sauce or a cumberland sauce (lemon, orange, redcurrant jelly and port). If you can get it locally you could make a cumberland sauce but instead of redcurrant jelly use Inverness sauce.
Reason why I am asking for a sauce is I know somepoeple like some fluid with their meal (my mum does) plan is to glaze the joint anyway.
Planning a smoked joint as I like the taste (like extra thick bacon )
This is what you do. Don't deviate from this recipe. It's amazing. We do it every christmas.
1. Buy nice big lump of gammon, make sure it's got skin on and a good 1/2 inch or more of fat. Also buy colemans powdered mustard, Soft brown sugar, Onion, bay leaves, cloves and a can of cider.
2. Tie up gammon (it might have a plastic sleeve on it, leave this on). Bring up to boil in large pan of cold water.
3. discard water, and refill (use half the can of cider too, make sure water is covering gammon). add a couple of bay leaves, peppercorns, and an onion studded with cloves.
4. Boil for 30 mins per half kilo.
5. Remove gammon, cut string off and remove skin (don't remove the fat, leave a good layer of it on). Score the fat in to diamond shapes.
6. Turn on oven.
7. For the glaze. Mix 3 or so tablespoons of mustard powder with water until it is a paste. Now roll your sleeves up and apply it all over the joint. Put loads of it on, don't hold back. Squeeze it in to all the cracks. Now, using your hands again, press in loads of brown sugar. The ham will still be hot and it will melt. Doesn't matter, just keep slapping it on.
Now get the cloves and stick one in to the centre of every diamond.
8. Stick it in the oven for 45 mins or so with a cm or so of cider in the bottom. Check up on it every now and then, baste with the juices, and if the ciders all gone then add a splash more or your pan will burn.
Serve with some nice veg and a light gravy (turnips, carrots, parsnips swede etc) or serve cold with other bits and bobs (cumberland sauce might be what you're looking for).
Also, get more gammon than you need, as it makes excellent ham the rest of the week (have ham egg and chips the next day. YUM!)