The park is named after Josef Sprinzak. Sprinzak was a leading Zionist activist in the first half of the 20th century, an Israeli politician, and the first Speaker of the Knesset, a role he held from 1949 until his death in 1959. [Wikipedia]
To find the cache, walk around the park until you find the outdoor gym. In front of the device shown in the picture* you'll see a short dirt path. Walk that path until you reach a big gravel area. The cache will be somewhere on your left - use the hint to find it! [note it's a link to a picture]
*if you can't see the picture, look for the yellow-colored part of the gym zone ground