"Pokemon that don't evolve" is taken to mean single-stage Pokemon, rather than those that have already evolved and cannot anymore. For the purposes of this answer, regional forms are distinct Pokemon and will be categorised under the generation they were introduced.
Ultra Beasts and Paradox Pokemon are also omitted from this list. If you're curious, most have a BST of 570, with a few Paradoxes having 590.
Generation I
Farfetch'd: 377
Kangaskhan: 490
Pinsir: 500
Tauros: 490
Lapras: 535
Ditto: 238
Aerodactyl: 515
Generation II
Unown: 336
Qwilfish: 440
Shuckle: 505
Heracross: 500
Corsola: 410
Delibird: 330
Skarmory: 465
Smeargle: 250
Miltank: 490
Generation III
Sableye: 380
Mawile: 380
Plusle: 405
Minun: 405
Volbeat: 430
Illumise: 430
Torkoal: 470
Spinda: 360
Zangoose: 458
Seviper: 458
Lunatone: 460
Solrock: 460
Castform: 420
Kecleon: 440
Tropius: 460
Absol: 465
Relicanth: 485
Luvdisc: 330
Generation IV
Pachirisu: 405
Chatot: 411
Spiritomb: 485
Carnivine: 454
Rotom (base): 440
Rotom (transformed): 520
Generation V
Audino: 445
Throh: 465
Sawk: 465
Basculin-Red and Basculin-Blue: 460
Maractus: 461
Sigilyph: 490
Emolga: 428
Alomomola: 470
Cryogonal: 515
Stunfisk: 471
Druddigon: 485
Bouffalant: 490
Heatmor: 484
Durant: 484
Generation VI
Furfrou: 472
Hawlucha: 500
Dedenne: 431
Carbink: 500
Klefki: 470
Generation VII
Oricorio: 476
Wishiwashi-Solo: 175
Wishiwashi-School: 620
Comfey: 485
Oranguru: 490
Passimian: 490
Pyukumuku: 410
Minior: 440
Komala: 480
Turtonator: 485
Togedemaru: 435
Mimikyu: 476
Bruxish: 475
Drampa: 485
Dhelmise: 517
Pikachu in a cap: 320
Partner Pikachu: 430
Partner Eevee: 435
Generation VIII
Stunfisk-Galar: 471
Cramorant: 475
Falinks: 470
Pincurchin: 435
Stonjourner: 470
Eiscue: 470
Indeedee: 475
Morpeko: 436
Dracozolt: 505
Arctozolt: 505
Dracovish: 505
Arctovish: 505
Generation IX
Tauros-Paldea (all): 490
Squawkabilly: 417
Klawf: 450
Bombirdier: 485
Cyclizar: 501
Orthworm: 480
Flamigo: 500
Veluza: 478
Dondozo: 530
Tatsugiri: 475