Certainly going to be difficult making a profit at it with those numbers.
What sort of birds are you looking at farmers wife?
It might be worth looking at pure breeds? Maybe some with a local connection or different breeds laying different coloured eggs for a little added interest and to justify a higher premium?
I don't know how much you've looked into this so apologies if i'm going over something you know already..
A point worth looking at here might be the egg supply throughout the year, especially if you have a regular customer base and don't want to lose them.
If you're breeding or rearing your own then you'll need to stagger your flock to ensure a regular egg supply.
Looking at it roughly, with a standard hybrid layer, for your 50 eggs a day you're looking at 60 birds in peak production (22 weeks of age ish)
over the next 60 weeks or so your 50 eggs a day will slowly drop to 30 eggs a day.
at this point the birds will likely stop laying and moult, so you're feeding them for a good few weeks with zero return (this is why commercial farmers get in new birds at this point).
But more importantly if you were selling 50 eggs a day at the start of the year then you now only have 30 eggs a day to sell so you lose customers.
Once they have finished moulting they will lay again, not quite as well as the first year but you should still get 40 eggs a day from them and the eggs will be a good bit bigger!
Fair enough starting off with a flock of 60 birds initially to get your egg numbers up to sell but in your place i'd be looking at having a flock of 80 birds in four groups of 20 all aged 20 weeks apart.
rear another 20 birds about 20 weeks younger than your main flock.
this would mean that when your main flock is 40 weeks old and has dropped to around 43 eggs a day, your younger flock will weigh in with another 18 eggs a day.
If you repeat the process every 20 weeks you'll end up with a steady flow of eggs.
Bit of a faff but the only way I can see you can keep the eggs coming in.
If you're keeping the older birds past the moult and into lay the following year it can work the same way, just needs a bit more calculations