These are two fairly standard types of hammers used by many dulcimer players. These are relatively simple and cheap - it would be quite easy to find hammers made out of 'exotic woods' available at suitably inflated prices, but whether they would actually sound any better or play any better is another matter!
This page shows the amazing diversity of hammers that have been traditionally used for playing the dulcimer and similar instruments in different countries (from Kettlewell's book).
Also from Kettlewell's book, this shows some of the things that can be used to hit the dulcimer strings in 'emergency' situations!
This is a totally amazing Youtube video by Ben Catt, which shows him playing the Irish Washerwoman using an unbelievable range of household items as 'hammers': spoons, forks, kazoos, ladles, fish sticks, fingers, ping pong paddles, chopsticks, penny whistles, pop bottles, 36" dowels, psaltery bows, scrapers, mallets, cleaning brushes, bones, zip ties and conventional hammers.
These hammers are the culmination of my experimentation process. They are perfectly balanced in the sense that when held in the white area the weight in front perfectly matches the weight behind, due to the counterbalancing screws that are attached at the near end. For me at least, this mid point grip gives greater control over the hammers. After several years of playing, I now find it quite difficult to use conventional hammers. Each to his own, as they say!