You need to check with the Fish and Game Commission's rules. Since you PA waters are inland and not navigable waters, with the exception of Lake Erie you need to conform to their regulations. This passage is taken directl from their website.
FIRE EXTINGUISHERS • Coast Guard-approved fire extinguishers must be carried on all motorboats 26 feet or more in length. • Motorboats less than 26 feet in length with gasoline engines are required to carry a fire extinguisher if they have one or more of the following: closed compartments, permanently installed fuel tanks, double bottoms not sealed to the hull or completely filled with flotation materials, closed living spaces or closed storage compartments in which flammable materials are stowed. Note: Open boats such as jonboats where an after-market solid wood or metal floor is installed and is not completely sealed to the hull are NOT required to carry a fire extinguisher. • Fire extinguishers must be installed so that they are immediately available, within arm’s reach of the operator or passengers on board. • Fire extinguishers must be maintained and fully charged.
I do not believe your boat is required to have one. I think you would be wise to take the time and read over all of their regulations
Pay attention to several important things. The first is the cold water life jacket requirement.
MANDATORY COLD WEATHER LIFE JACKET WEAR • From November 1 through April 30, boaters are required by law to wear life jackets on boats less than 16 feet in length or any canoe or kayak. This regulation went into effect in 2012 and is intended to protect boaters from the dangers of cold water shock if they fall into the water. Recreational boating fatalities that occur in Pennsylvania from November through April are primarily due to the effects of cold water immersion. When water temperatures are less than 70 degrees F, cold water shock is a major factor in boating fatalities. Victims who wear life jacket when exposed to cold water have potentially life-saving advantages such as insulation from the cold, buoyancy for victims who are unable to tread water and reduced risk of aspiration of water. In an effort to reduce the number of fatalities related to cold water immersion, the Commission has amended regulations to require life jackets to be worn on small and unstable boats during the period most noted for cold water temperatures.
Also be aware of the boaters safety course requirements. Depending on your age you could be required to take a course and have proof of it with you anytime you boat.
MANDATORY BOATING EDUCATION HP of Motor Restrictions of Use PWC* All PWC (personal watercraft) operators, regardless of age, must have in their possession a Boating Safety Education Certificate. Persons 11 years of age or younger may NOT operate. Persons 12 through 15 years of age may NOT operate with any passengers on board 15 years of age or younger or rent a PWC. *Also known as Jet Ski®, Sea-Doo®, WaveRunners®, Tigershark® and others.
Boat 0 - 25 hp None
Boat 25 hp and greater Persons 11 years of age or younger may NOT operate. Persons born on or after January 1, 1982, may not operate unless they have obtained and have in possession a Boating Safety Education Certificate.