I don't know the murdick minnow, and I've never tied with EZ sparkle, but if you have hooks, a little tinsel, and a few colors of bucktail you can tie all the sand eels patterns you want.
My goto sand eel for a long time has been a VERY sparse bucktail streamer tied in the Joe Brooks "Blonde" style. You can google "Joe Brooks Blonde" and find all sorts of color combinations.
The fly is very simple--a bucktail tail (with or without a little crystal flash or flashabou); a tinsel body (I like pearl, but silver will do), and a bucktail wing.
When I say sparse, I mean sparse--perhaps a dozen strands of hair in the tail, and another dozen in the wing.
I'm partial to two color combinations, both with white tails. The first has a wing of olive over yellow; the other has a wing of olive over blue. Sometimes I put a few strands of peacock herl to get a darker back.
If you want another simple and very effective fly for stripers on sand eels, Google "Ray's Fly".
Again, the sparser the better if you are matching sand eels (or silversides).
There are lots of flies out there to match various baits, but tie a variety of sparse bucktails and you'll have most of the small baits pretty well matched. Feel free to mess with epoxy and EZ body and mylar tubing and all sorts of other stuff. You can make great looking flies and they'll catch fish. But the simple bucktails will fish just as well, and you can tie a dozen of them in an hour.