As you probably know, acrylic screw capsules are easily obtainable from dealers. The capsules can be housed in an ex proof set case, also obtained from a dealer. The capsules that I get from a dealer are second hand, of various sizes and are retrieved from broken proof sets.
So far as a case to hold the capsules is concerned, the case size depends on the number of acrylic capsules you need to house. What follows below is only suitable for up to about six coins, because proof set cases are rarely larger than this.
I modified an ex proof set case with snap close lid. The case originally held a silver proof set containing capsules of different sizes.
I purchased a piece of off cut aluminium plate 6mm thick from a scrap metal dealer, and cut holes into it large enough to hold six capsules of the same size, with allowance for velvet lining. Velvet of the colour you want is easily obtained from a craft or materials shop. Underneath this holed plate was another of the same thickness but without holes, also covered in velvet.
The extra mass of the aluminium plate in the case has very substantial and satisfying tactile feel to it.
One problem I have in answering this is that I do not know of how many proof silver Dollars that you have; this will determine the size of the metal jewel case. The other problem is that such a collection has to be small in number, and should present as a complete collection in itself. Maybe it is that you wish to expand on this collection of proof dollars and so this presentation would be of little use to you. If that is so, perhaps I may have inspired someone else in the presentation of coins in this manner.
I will post pictures of my work here in a few days.