Yes, sending it to Strong is a good idea.
National has a 20 year service life so they won't repack it for you. All the manufacturers except Strong Enterprises have a service life limit on their equipment.
A 27 year old National is a pretty old parachute. Just saying.. But, having said that, if Strong repacks it and signs it off (for another 180 days only!) I wouldn't have any qualms about wearing and potentially using it.
You can find the packing data card under the pin protector flap. It's the triangular shaped flap on the back of the parachute towards the top. Lift the velcro'd edges and unfold the flaps.
RV-3 N333LT - 500hrs PIC
AFF Skydiving Instructor (Ret)
IF1 Reno Racer (Ret)
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A&P / IA
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