To my knowledge, there was not much of an issue with the scale of US aid to the UK in the post war period. It was the largest beneficiary of the Marshall Plan, despite being significantly less destroyed than most other countries involved. The problem was more that that money was spent on nationalisation and maintaining Britain's place in the world than meaningful long term modernisation of industry, which was what was needed.it is a tough call though fascinated by the idea of Gaitskell living long enough to become PM in 1964, perhaps success would have prompted the likes of Peter Shore to recant his support of the CND (instead of later in life) in order to elevate his position within the party along with other pro/anti-EEC candidates.
One other idea for a Labour dominated decade in the 1950s would be Attlee during the 1945 Elections winning a 1950-like majority only to be defeated a year or so later by Winston Churchill, with the US being more inclined to provide significantly more post-war aid then they did in OTL (where Churchill and others had to basically pursuade the US to provide the post-war aid they did despite the Attlee government holding a large majority). Attlee is thus subsequently replaced by Hugh Gaitskell who after battles over Clause IV, etc eventually leads Labour to dominate the 1950s and thus move the party towards a Gaitskelite direction.
Pragmatism and a recognition it is better to work within the Labour tent than outside of it are hallmarks of Bevanism, so that side of the party is largely going to stay put.Which would have put the UK on a better domestic / economic footing into the next decade (together with adopting Barbara Castle's 1969 In Place of Strife white paper and removing Clause IV) compared to OTL, though am interested in seeing how token British involvement in Vietnam, no Clause IV and adopting In Place of Strife would have affected the Bevanite / Bennite wing on the Labour party and whether we'd see the Bennite equivalent of an independent SDP breakaway emerge (with fractures between the remaining Gaitskellite and Jenkinsite wing over Europe potentially helping to revive the Liberals in tandem with Pro-EEC Tory breakaways).
A Bennite breakaway is hard to do during this period, largely because the hard left were in the ascendancy throughout the 1960s and 1970s, and would therefore have very little reason to leave a party it looked set to inherit anyway. Part of the reason why they rose to prominence can be attributed to the perceived failings of successive Labour governments, which would be less of an issue ITTL, but they were also down to deeper trends like the replacement of one generation of moderate activists with another which had largely been influenced by 1960s counter culture- which is not going away, and would if anything get stronger if Gaitskell involves Britain in Vietnam. Add to that the economic problems we would still probably see in the seventies and trade union resentment at In Place of Strife, and you probably have a recipe for an equally strong hard left insurgency in the late seventies and early eighties.