Top 10 Best Skeleton and Open Heart Watches Under $500 - WatchReviewBlog
Seiko Presage SSA443 SSA443J1 Zen Garden Open Heart White... for $470 for sale from a Seller on Chrono24
My Eastern Watch Collection: SEIKO 5 Sports 100M Retro Automatic Open Heart SSA327K1 (similar to SSA329K1, SSA331K1, SSA333K1 & SSA335K1) – A Flexible Watch, A Review (plus Video)