These SY accumulator sphere kits are stocked by BTW for rebuilding customer spheres but we also sell them at cost as a service. These kits are from Flying Spares and include the new, much improved sealing arrangement. These kits are not for later SZ throwaway spheres.
Rebuilding spheres takes special tools which are availale from BTW but we are also happy to do it for you. Sphere exchange starts at $350 ea. which includes the price of the kit. Turnaround is usually less than a week.
I recently created a forum post describing the sphere rebuilding process:
SY Accumulator Sphere Rebuild Kit
All US shipping is $8.55 - no matter the size.
Please contact us for an accurate international quote.
Please see the shipping FAQs for detailed shipping information.