There are no absolute rules which dictate which pin to use for a particular type of lace. Suit the thickness of the pin to the thread you are using to produce a result which you find pleasing.

17mm x 0.45mm x 25g packet yellow brass 'Duchesse' pins. - Not Available.
The manufacturer is not able to supply this size pin, of suitable quality, at present.

 -

30mm x 0.50mm x 50g box nickel plated pins.

 £4.00

10mm x 0.55mm nickel plated, box of 1000 pins.

 £2.50

26mm x 0.55mm x 15g pack brass pins.

 £1.85

26mm x 0.55mm x 25g pack brass pins.

 £2.50

38mm x 0.55mm hardened & tempered black steel, box of 100 pins.

 £1.00

26mm x 0.58mm stainless steel, box of 225 pins.

 £1.75

14mm x 0.60mm nickel plated, box of 800 pins.

 £2.50

18mm x 0.60mm x 25g packet nickel plated pins.

 £1.75

39mm x 0.60mm x 25g packet yellow brass pins.

 £2.50

26mm x 0.65mm x 25g box yellow brass pins.

 £2.50

26mm x 0.65mm x 100g box yellow brass pins.

 £6.00

26mm x 0.75mm x 100g box nickel plated brass pins.

 £5.60

38mm x 1.05mm mild steel nickel plated, packet of 18 pins.

 50p