hi there, sorry for the delay in answering – but – I have just been doing a bit of research on the launch. I take it that the plan that your father worked from is the one in the image that I am going to put on which I have scanned from Model Boats magazine, February 1984. I am unsure if you have this issue from your dad to go along with the plans, but, if not there are several places that you will be able to obtain the issue of the Model Boats Magazine on the web. As far as fittings go; and manufacturing of the fittings yourself and detailed plans – I am sorry to say there is very little information around. But, depending on which version your father had been building – because – I note that there is one version that has a dinghy on the back and also no gun turrets on the bridge – then there is the lower version which seems to have an Oerlikon gun on the rear end plus the Perspex turrets on the bridge which normally have twin guns in them.
I know there are a lot of people who try to manufacture these Perspex domes out of old light bulbs – some of them are pretty successful – but the last pair I actually made I moulded them using the oven in the kitchen and a mould – if you go onto Mayhem and look on Masterclass for the RAF launch build there – you will see how this is done.
If you wish to purchase fittings – I know there is a Company called Battlecraft – who do a lot of fittings for this type of craft – and at the right scale.