It does look a bit more unique than the M-Type Submarine
from Gihren's Greed. That version already had the rear hatch for the Mad Angler's
MS Hanagr, though the MSV-R design would seem to indicate that it wasn't part of the original design.
I can't read the text either, though I can see some numbers:
-0075, 8, 0076, 1, 2, 0077, 3, 0077, "1, 2, 3", "4, 5, 6", 0079, January 3rd/March 1st, 0079
If I had to guess:
I would say that maybe on U.C. 0075 the Federation comissioned the production of 8 of these submarines. Production of the 1st and 2nd submarines began in 0076, while production of the third began on U.C. 0077. These 3 submarines were completed on the same year, while the 4th, 5th and 6th units entered production soon afterwards.
The date most likely refer to either the beginning of the war, or the beginning of the Earth Invasion.