I fly an SZD-59 which is the same fuselage as Jantar3... which is very similar to Jantar2 and I think uses the same seatback/headrest. I used a Mini (up to 180#) Softie Wedge backpack that is extremely comfortable in this ship. It's a super nice parachute and I hate to sell it but I'm not currently flying.
Hasn't been packed or worn in a long time, but has always been stored in a controlled climate/indoors. Black container, black carrying bag. Alan Silvers sewed bright yellow toggles onto the steering risers for added safety.
It will be 10yrs old this July. Asking $1200, and I'm also in your neck of the woods. pm me at: paul at eaglebrandproducts dot com for more details.
https://i.imgur.com/du9OvED.jpg
https://i.imgur.com/iY19xtA.jpg
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https://i.imgur.com/kmORHXW.jpg