The calculated distance (air line) between Mazār-e Sharīf and Rustāq is approximately 153 miles respectively 246 kilometers.
By car or train, the actual journey to Rustāq is certainly longer, as only the direct route (as the crow flies) between Mazār-e Sharīf and Rustāq has been calculated here.
Air line (approximately)
246 kilometers
133 nautical miles