I recommend looking up the part number and asking for it. They might have the dusty old fiche somewhere but my experience with parts counter people lately is not good when asking about a model out of production for 35 years. Example - 74 CB750 main jets are 991142460XXXX (110 jet = 1100, 105 jet = 1050); slow jets 99124076XXXX (same, #40 = 0400).
This is for one type of carb: check the fiche for your model and year (at CMSNL.com or other sites with parts lookup) and get the correct part number. All KeiHin jets in the Honda part numbering scheme work the same way, a base number and then the size. Jets from Honda are genuine OEM KeiHin parts, not the "close but no cigar" ones from Sirius etc. Many possible sizes are unobtainable although they used to stock several "non-stock" jets. Exchange was always at the pleasure of the dealer, and I doubt any dealers stock these any more to offer exchange.
The multi size jet kits available are a good deal, if you tune with those jets then it's not important that their #110 may be different from a KeiHin #110. If you know somehow that you need a #110 then in my experience only a real KeiHin #110 is reliably a Keihin #110 size and flow.
Avoid non-OEM metering needles.