A rare R1a1 Y-haplogroup (Y-HG) L657 clade subtype designated as LPKSTR is found in most male members of a clan of "founder" families within the Goud Saraswat Brahmin community in Lotli town in Western India. TMRCA calculations using pairwise comparisons to control cohorts suggested a probable migration history distinct from the canonical narrative for medieval migration of orthodox Brahmin families to South India. Using Y-HG centroid analysis, chi-square analysis of TMRCA distributions and archeological find-spots, and discriminant function analysis we show that the parental Z93 L342.2 subclade in which LPKSTR occurs originated in West Asia and that LPKSTR individuals migrated toward the southeast by a Bolan Pass route distinct from the traditionally presumed route of Brahmin ingress into the Indian subcontinent. The proposed migration route is supported by archeological, toponymic, numismatic, linguistic, iconographic, and literary data. Lastly, we present cultural metrics demonstrating that these LPKSTR lineages retained distinct family practices with respect to literacy, religious practice, and emigration not shared with orthodox Brahmins of canonical geographic origin within the same community, despite centuries of intermarriage. Long-term transmission of differentiated family practices within a patrilineal endogamous community has rarely been documented.