Is there a plastic men's urinal that fits over the seat in a home toilet?

It should be about 10 inches wide, 18 inches long and 12 inches high with a funnel at the bottom to direct the urine into the standard water closet. And it should fit snuggly over the toilet seat.
There are hand held urinals, that are uncomfortable to use. I am talking about a larger fixture that in essence raises up the the opening of a regular toilet to where old men can straddle the urinal and not miss when they have to pee.

As much as I might empathize, and as descriptive as Sunshines answer is, I more agree with comments by others, with no offense meant.

I'm an OLD man, and if I can't stand to urinate, or manage to sit on a toilet seat, and/or can't control my aim into a bowl opening as large as a toilet, then I need assistance.

Beyond that thought, I would hope that there is a service available after EVERY visit to the WC, to clean up.

I suppose, even for the demeted, one could sprinkle cheerios in the bowl as targets, turning it into a game.

We have to hope not - the sanitation of it without attached water flow would be a horror. Taking it off for normal use would involve setting it on the floor or on or in the basin. A slightly better choice would be a replacement for the lid and seat which would hold the funnel off to one side and use a small tube to carry the urine into the bowl while still allowing the lid and seat to be raised - a slick tube would improve sanitation and permanently mounting would eliminate the setting down - the right size and slickness would allow a glass of water (after washing ones hands) to do a proper "flush".

Put down newspapers at the base of the toilet until you find another solution. Then all you will need to do is change paper.
OR
Put a gallon jug with a big opening in the bathroom and tell the old men to use that. Be sure to include the cap and train them to cap when finish. Leave a bell in the toilet and when they are done, tell the old men to ring the bell and you will come to empty jug.

In the states it's called a "hat". It's a white plastic piece that fits over the sides of the toilet, covers the entire inside, and fits down inside the toilet. It's used to collect urine for measuring. The toilet seat then comes down and holds the sides of it down on the toilet. Another option for an older man to collect urine is called a "condom catheter" which fits over the penis and collects urine, which then flows into a flat bag attached to the side of his leg. It's great for men who tend to dribble throughout the day and don't want to wear a "pad". I hope this helps.

Just pee in the grid. That way you don't even have to go upstairs.

gross