Is it permissible to buy cats toys that have eyes sewn or printed onto them e.g. Toy mice, for them to play with? Also, is it permissible to buy cats food that does not contain halal meat (but is not pork) e.g. Chicken, turkey, beef dry/wet food, or does this food have to be halal (as this is not sold in the UK?

Praise
be to Allah

Firstly:

It is prohibited in general terms to keep images, and we are
instructed to erase their features, as in the hadith of Abu’l-Hayaaj al-Asadi
who said: ‘Ali (may Allah be pleased with him) said to me: Shall I not send
you on a mission like that on which the Messenger of Allah (blessings and
peace of Allah be upon him) sent me? Do not leave any image without erasing
its features or any built-up grave without levelling it. The Messenger of
Allah (blessings and peace of Allah be upon him) refused to enter the house
of ‘Aa’ishah when she acquired a cushion on which there were images; and he
tore down a curtain on which there were images and stated that the angels do
not enter a house in which there is a dog or an image. There are many
well-known hadiths on this topic in as-Saheehayn and elsewhere.

No exception is made from the prohibition on keeping images
except what has been narrated about it being permissible in the case of toys
for little children. This has been explained in detail in the answer to
question no. 119056.

So if you erase the facial features from these toys, then the
prohibition no longer applies, and it is permissible to keep them.

But if you do not erase the facial features, then it is not
permissible to buy them or keep them, whether for cats or for adornment or
for any other purpose, apart from that which is permitted in Islamic
teaching, which is for small children to play with them.

See the answer to question no. 72915

Secondly:

It is permissible to feed cats dead meat [that which is not
slaughtered in the prescribed manner], pork and so on, and it is not
stipulated that the meat should be slaughtered in the prescribed Islamic
manner. So if you find such meat thrown away, or it is given to you for
free, then you may give it to the cat. As for buying it, that is not
permissible, because of the report narrated by al-Bukhaari (2236) and Muslim
(1581) from Jaabir ibn ‘Abdullah (may Allah be pleased with him), who heard
the Messenger of Allah (blessings and peace of Allah be upon him) say:
“Allah and His Messenger have forbidden the sale of alcohol, dead meat, pork
and idols.”

An-Nawawi (may Allah have mercy on him) said:

It is permissible to feed dead meet to hunting birds, but it
is not permissible to sell it.

End quote from al-Majmoo‘ (9/285)

Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) was asked
about canned cat food that contains pork; is it permissible to buy it and
feed it to cats?

He replied: If that means buying the cans, then it is not
permissible, because it is not permissible to pay the price of pork and buy
it.

But if someone finds it thrown away, and feeds it to his cat,
then there is nothing wrong with that. And Allah knows best. End quote.

And Allah knows best.