Yeah if you're not a big fan of foils, you just want the mechanically unique cards its 1-191. For all the non-foil, non-extended, non-alt-art cards you would need 1-331. If you bought them as singles that would be $342 as of today (source: MTG Goldfish )
Note you would get all of those in one swoop if you just purchased the four Commander Decks.
This would run you $180 on Amazon
If you wanted to add the alt-art it would include 535-565. The non-foils of these are atually quite cheap.
Singles only would run you $37 (source: MTG Goldfish )
So in summary, you could get all the non-foil, non-extended cards and showcase cards for about $210 if you get lucky with bundle order for singles on TCG or similar.