Amazon.com: MAKELEN Shimano Thumb Shift Lever SL-TX30, 21 Speed-Right 7 Speed Left 3 Speed (No SIS) Thumb Gear Bike Shift Lever for Mountain Bicycle : Sports & Outdoors
Shimano Tourney TX800 Rear Derailleur 7/8 Speed For MTB Mountain Bike Bicycle RD-TX800-SGS Compatible SIS Index Shifting - AliExpress
New 7 speed commuter with Shimano SIS index. No noise on stand, shifts smoothly but low clanking sound on road when pedaling in 4th & 5th though not other gears : r/bikewrench