The half-the-price rule is a bad rule. What matters is the age of the machine, which part failed, and whether the failure is in a system that is about to fail again.
The number on the retailer page is not the number the manufacturer's support site indexes. That one difference explains most "model not found" lookups.
Before you buy a part or argue about a warranty claim, get the numbers right. These are the fields that actually decide whether a part fits and whether a repair is worth doing.
Type
is the loading direction. A top load machine has a lid you lift and an agitator or washplate inside; a front load machine has a horizontal drum and a door seal. The two behave differently in service: top loaders are cheaper to repair and use more water, front loaders use less water and need the door boot wiped down to stay odour-free.
Capacity
is the drum volume in US cubic feet. As a working rule one cubic foot takes about 3–4 kg of dry laundry, so a 4.5 cu ft drum handles a queen bedding set and a 2.0 cu ft compact unit is a one-person or apartment machine.
Dimensions
are height by width by depth in inches, without hoses. Allow an inch on each side and four to six inches behind for the fill and drain connections when you are checking a cut-out, and measure the doorway on the route in, not just the final spot.
Choosing between models
In practice the choice comes down to three things: whether you have room for a front loader to swing its door open, how large a single load you need to wash, and whether the machine sits on a floor that can take a spin cycle. A second-floor wood floor amplifies vibration; a top loader with a suspension system copes better than a compact front loader bolted to joists.
Water and energy use differ more than the marketing suggests. The annual gallon figures for these models range widely, and over five years that gap is the single largest running-cost difference between two machines that cost the same at retail.