It's a current-production part — no obsolescence concern for BOM planning.
Sizing and derating — the real numbers
At 40 °C it derates to 9.43 A; at 50 °C to 8.82 A. If your panel runs at 45 °C (common in a sealed enclosure), you're at 9.13 A continuous — so a 10 A load would need a larger frame. Touch-protected terminals and IP20 with conductors connected are standard; sealable for lockout/tagout.
The 5SL4120-7CC is a 2-pole C-curve 20 A breaker — different pole count, curve, and amp rating. The 5SL6310-8CC will not drop into a panel wired for that 2-pole without reconfiguring the busbar and checking the load's inrush characteristic. Stick with the 5SL6310-8CC for a 3-pole D-curve 10 A position; if you need a 3-pole C-curve at a different current, the 5SL series has variants for that.