I tend to " life " parts as I'd rather change them on my schedule and not at random.

113 K is well within in the failure window, I bought my 97 SL320 at 124 K and the pump was starting to leak.

When you do the pump, change as many hoses as possible. I bought all of the hoses at the dealer and the pricing was what you would expect for a Chevy at a generic auto parts. The limiter here is that I deleted the expensive looking heated window washer tank and windshield molded " T " hoses as my car is summer only. Talk to the dealer parts guy, many times they can put your order under a garage discount if you look the part and order a pile of stuff.

I also added a second valve to the heater core so it does not get hot under the dash. The SL heater core has large in and out hoses plus a small bleed line, this bleed line allows coolant to circulate even when the stock valve is closed.

Also get a grease needle and lube the idler pulleys with one pump, this will keep them going. ( Don't put in too much grease, the added friction will burn the grease causing it to degrade. )