Ya'.....
It seems like every day someone decides to "assemble" their very own 1911 platform pistol. I have no idea what your experience is, but the 1911 wasn't designed to be assembled, it was designed to be built by individuals working in a large factory (Colt's) that had considerable training, and worked under a master before being allowed to do the job on their own.
In this day and age, "assembling" a gun tends to mean that you have all of the parts laid out on a bench, and you put them together like a puzzle. Some more recent firearms have been set up this way so that the manufacturer can lower labor costs by not having to use so much skilled workers.
The folks that did (and do) make 1911's for a living also had (and used) an extensive collection of special tools, fixtures and gages to insure things went right. Lockwork was not supposed to be a drop-in affair. This is even truer today because aftermarket parts often have extra metal added at certain places to facilitate individual fitting.
Caspian make excellent parts, and yes, it would be a good idea to buy a matching slide and frame from them. While I was at it I would have them lap the slide and frame together because they have a fixture for doing this, and I doubt that you do. I would also pay them to mill the slide with dovetails to match whatever sights you have in mind, and to install the grip screw bushings and plunger tube. What they charge is a lot less then buying the necessary tools to do the job yourself.
And unless you are loaded with bucks ($$$) I wouldn’t send any extra money for custom cosmetics on a first gun. It is very easy to make a mistake and ruin something. In fact if you are determined to go ahead it might just be a good idea to consider putting a Damascus slide on say, a Colt pistol (or whatever clone you like) along with sights of your choice.
But then, it’s your money…
