2001 S40 Front main seals

[Stilltrying2]

2001 S40 148k on the clock
Replaced in last 3-4 Years, for reference
** Oil Trap / PCV Box / Breather Box - all associated parts
** Timing Belt, Tensioner, Idler, VVT Gear, 3 Camshaft seals, 1 Crankshaft seal, 2 Hoses to Oil cooler, Serpentine Belt, Replaced new/oiley U-shaped PCV hose with original/better shape
** Fuel Pressure Regulator
** Flex pipe – welded new one on – now car is quiet !
** Both Engine Coils
** Ignition wiring harness – due to shutting off, sputtering, and start issues
** Blown Head gasket .. Mechanic pulled the head, sent it out to be cleaned, resurfaced the head, machined the valves and seats, adjusted valves, installed new valve seals, installed a thermostat kit, and threw in a new coil.
** Cost for above = $zero$ = long story
** Sway Bar Bushings, Steering Rack Boots
** Oil Cap Gasket

Current Issue = very minimal oil leak
Mechanic says it is the front engine seals

** Assuming this is the answer - how long before the seals blow and blow up the engine ?
** What else can I replace while he is "down there" replacing he seals ?
** I also need a Suspension Strut Bumper = an expensive repair
... I can't find a "Quick Strut" which would be a quick plug and play repair

Thanks much for your help or comments.

Tom in Carolina