Firstly, court costs for possession are fixed, unless specifically allowed for in your tenancy agreement. You have a social landlord, therefore the costs are fixed and quite low in comparison to the actual cost to the LL. In other words, most of that £2500 is rent arrears.
This means you have not paid the shortfall on your rent for well over a year.
I say this as the first step towards sorting your issues out is to acknowledge and accept that you have not done what you are supposed to do, which is pay the shortfall and an amount towards the arrears. £167 is the shortfall plus £7 a month towards the arrears - unless you are saying they wanted you to pay the shortfall £37 a week, plus £167 a month? If the latter, then yes, it was a bit unreasonable as a social landlord can accept a minimum amount towards the arrears - current rate for UC is 5%.
The second step is to sit down and work out your income and expenditure. StepChange provide an excellent budget sheet, which you will find here: www.stepchange.org/Portals/0/img/debt-info/income-and-expenditure-form-example.pdf
You must PRIORITISE your outgoings. Rent and Council Tax are your first priorities - the first because, as you've discovered, they can take your home away, and the second because they can put another type of roof over your head ultimately (prison). Therefore these are the two payments that must be made FIRST every week/month.
No one can put you in prison or take your home from you for civil debts, so any credit cards, store cards, loans, overdrafts or the like are low priority debts and you should write and negotiate lower payments that fit your income.
Utilities must be paid as the second priority - all utility companies will allow you to pay monthly to help you budget, if you are not already doing this, contact them to arrange it.
The budget sheet will help you to set out everything you have outgoing and it will then be up to you to see what can be reduced or stopped in order to help you pay a) the shortfall in the rent between the housing benefit and the actual rent and b) something towards the arrears.
As you are on benefits, there is a minimum amount the court would ask you to pay towards the arrears (as stated above).
Whilst you have priority band B for moving, you will not be moved whilst you have rent arrears, so the sooner you clear them the sooner you will be able to move.
You cannot sort this out until you make a budget plan - so get started now and then you'll be able to approach your landlord with a reasonable offer. If they refuse, you'll need to apply to the court for a stay of eviction and hopefully the court will give you a further opportunity to show you can be responsible.
If you're evicted, you will have made yourself intentionally homeless and will not be eligible for further social housing. You want to avoid this at all costs as private renting is going to be far more expensive than social housing and you are showing you cannot afford the latter, so definitely won't be able to afford the former.