Here are two more. I’ll mention that they are sold at much lower price points than Retro 51’s offerings.
The Xonex Crossword pencil and Autopoint Sudoku pencil both convey fun and practicality – bold graphics, and uncapped oversize erasers (unusual in mechanical pencils), for those of us who like to be able to correct our mistakes.
The Autopoint features 0.9mm lead, with a tube of B grade refills and three replacement erasers. It is made in the USA.
The Xonex has a more modern 0.7mm diameter lead, with unstated grade refills, and six replacement erasers. It is made in Taiwan.
Both seem solid, and good values for their price. The Autopoint is thinner, longer, and more traditional in appearance. The Xonex is definitely on the modern side. I also like the Xonex’s vinyl eraser, though the grey Autopoint eraser also works quite well!
Their packaging is not as elaborate as that of the Retro 51 (especially the near-generic Autopoint), but either would make a fine gift.